Publications by authors named "MacGregor Thomas"

Article Synopsis
  • Inflammation might cause problems in the brain that lead to major depressive disorder (MDD).
  • Researchers used a special imaging technique to study the brain's white matter in 176 people with MDD and found that higher levels of inflammation were linked to worse white matter health.
  • The study suggests that inflammation can negatively affect important brain pathways, possibly contributing to MDD symptoms.
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Background: Chyle leaks following oesophagectomy are a frustrating complication of surgery with considerable morbidity. The use of near infra-red (NIR) fluorescence in surgery is an emerging technology and the use of fluorescence to identify the thoracic duct has been demonstrated in animal work and early human case reports. This study evaluated the use mesenteric and enteral administration of indocyanine green (ICG) in humans to identify the thoracic duct during oesophagectomy.

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Fast pixelated detectors incorporating direct electron detection (DED) technology are increasingly being regarded as universal detectors for scanning transmission electron microscopy (STEM), capable of imaging under multiple modes of operation. However, several issues remain around the post-acquisition processing and visualization of the often very large multidimensional STEM datasets produced by them. We discuss these issues and present open source software libraries to enable efficient processing and visualization of such datasets.

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Objective: To evaluate the bioequivalence (BE), safety, tolerability, and adhesion of Oppanol® polyisobutylene (PIB)-containing transdermal therapeutic system (TTS) formulation (test treatment, T) with VistanexTM PIB-containing TTS formulation (reference treatment, R) of clonidine.

Methods: This randomized, double-blind, 2-way crossover study comprised a 7-day treatment with 0.3 mg clonidine/24 h (T1/R1), a 7-day washout, and another 7-day treatment (R1/T1) period.

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How chemotherapy affects carcinoma genomes is largely unknown. Here we report whole-exome and deep sequencing of 30 paired oesophageal adenocarcinomas sampled before and after neo-adjuvant chemotherapy. Most, but not all, good responders pass through genetic bottlenecks, a feature associated with higher mutation burden pre-treatment.

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Purpose: Nelfinavir, a PI3K pathway inhibitor, is a radiosensitizer that increases tumor blood flow in preclinical models. We conducted an early-phase study to demonstrate the safety of nelfinavir combined with hypofractionated radiotherapy (RT) and to develop biomarkers of tumor perfusion and radiosensitization for this combinatorial approach.

Experimental Design: Ten patients with T3-4 N0-2 M1 rectal cancer received 7 days of oral nelfinavir (1,250 mg b.

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Objectives: To (1) evaluate educational needs of clinical students at Al-Quds University Medical School in the West Bank; (2) address these needs where possible using synchronous distance learning, with clinicians in Oxford providing case-based tutorials to undergraduates in the West Bank via an online platform (WizIQ) and (3) assess the impact of this education.

Design: Review of online OxPal Medlink database for tutorials held between March 2012 and April 2013. Needs assessment and evaluation of student and tutor experiences through online questionnaires, focus groups and semi-structured interviews.

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Aims: To provide model-based clinical development decision support including dose selection guidance for empagliflozin, an orally administered sodium glucose cotransporter 2 inhibitor, through developed exposure-response (E-R) models for efficacy and tolerability in patients with type 2 diabetes mellitus (T2DM).

Methods: Five randomized, placebo-controlled, multiple oral dose studies of empagliflozin in patients with T2DM (n = 974; 1-100 mg once daily, duration ≤12 weeks) were used to develop E-R models for efficacy (glycosylated haemoglobin [HbA1c ], fasting plasma glucose [FPG] and urinary glucose excretion). Two studies (n = 748, 12 weeks) were used to evaluate tolerability E-R.

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Background: To compare steady-state (ss) pharmacokinetic targets of nevirapine extended-release (NVP-XR) tablets once-daily (QD) with immediate-release (NVP-IR) tablet or oral suspension twice-daily in HIV-1-infected children and adolescents.

Methods: Phase I, open-label, multidose, cross-over study with optional extension phase, in 85 patients 3 to <18 years of age, previously on an NVP-IR-based regimen for ≥18 weeks with baseline viral load <50 copies/mL. Patients were stratified by age, treated with NVP-IR twice-daily for 11 days, then NVP-XR QD for 10 days.

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As the options for systemic treatment of malignant melanoma (MM) increase, the need to develop biomarkers to identify patients who might benefit from cytotoxic chemotherapy becomes more apparent. In preclinical models, oxaliplatin has activity in cisplatin-resistant cells. In this study, we have shown that oxaliplatin forms interstrand crosslinks (ICLs) in cellular DNA and that loss of the heterodimeric structure-specific endonuclease XPF-ERCC1 causes hypersensitivity to oxaliplatin in mammalian cells.

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Data from five randomized, placebo-controlled, multiple oral dose studies of empagliflozin in patients with type 2 diabetes mellitus (T2DM; N = 974; 1-100 mg q.d.; ≤12 weeks) were used to develop a population pharmacokinetic (PK) model for empagliflozin.

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Objectives: The aim of this analysis was to show the applicability of a newly developed algorithm to assess the influence of genetic variants and other covariates on nevirapine's drug disposition. The algorithm combines high-throughput genotyping data and nonlinear mixed effects modeling methods.

Methods: Patients, who participated in the 2NN pharmacokinetic sub study, were reconsented and reenrolled into a clinical trial for genotyping analysis.

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Introduction: Concerns about the decline of surgical research have been expressed in parallel to the debate on the future of academic surgery in the United Kingdom. The aim of this study was to survey the output of UK surgeons in ten high impact general surgical journals between 1987 and 2009 to estimate whether less clinical academic activity is occurring.

Methods: Ten general surgical journals with consistently the highest impact factors (1.

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The objective of this study was to evaluate the pharmacokinetic interaction of ritonavir-boosted BILR 355 (BILR 355/r) with emtricitabine (FTC)/tenofovir disoproxil fumarate (TDF). This was an open-label, prospective study. For Group A, 26 healthy subjects were given FTC/TDF (200/300 mg) once daily (QD) for 7 days and then co-administered with BILR 355/r (150/100 mg) twice daily (bid) for an additional 7 days.

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Objective: This study assessed the single-dose pharmacokinetics of the herpes antiviral acyclovir (administered as the pro-drug valacyclovir) alone and in combination with twice-daily 200 mg ritonavir-boosted tipranavir (500 mg) at steady state.

Methods: The study was an open label, one-sequence cross-over pharmacokinetic study in HIV-negative adults. Plasma drug concentrations were measured by validated LC/MS/MS assays; pharmacokinetics (AUC, C(max)) were determined using noncompartmental methods.

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The objective of this investigation was to evaluate the pharmacokinetic interaction of lopinavir/ritonavir (LPV/r) with BILR 355. In group A, 26 healthy participants were administered LPV/r (400mg/100mg) twice daily for 14 days, followed by coadministration of BILR 355, 150 mg twice daily for an additional 7 days. Pharmacokinetic assessments were performed on days 14 and 21.

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Purpose: This study characterized the pharmacokinetic effects, safety, and antiretroviral activity of three different doses of the nonpeptidic protease inhibitor tipranavir, in combination with ritonavir administered twice daily for 28 days, on a number of triple-combination regimens containing a nonnucleoside reverse transcriptase inhibitor (efavirenz or nevirapine) plus two nucleoside reverse transcriptase inhibitors (abacavir, didanosine, lamivudine, stavudine, and zidovudine) or a three nucleoside reverse transcriptase inhibitor combination (zidovudine, lamivudine, and abacavir).

Methods: The study enrolled 208 HIV-1-positive patients who had been on stable antiretroviral treatment for at least 12 weeks prior to study entry and had an HIV-1 RNA load of delta 20,000 copies/mL. The patients were randomized to receive one of three dose combinations of tipranavir and ritonavir (1250/100 mg, 750/100 mg, and 250/200 mg) in addition to their antiretroviral (ARV) regimen for the next 22 days.

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An in vitro-in vivo correlation (IVIVC) for four nevirapine extended release tablets with varying polymer contents was developed. The pharmacokinetics of extended release formulations were assessed in a parallel group study with healthy volunteers and compared with corresponding in vitro dissolution data obtained using a USP apparatus type 1. In vitro samples were analysed using HPLC with UV detection and in vivo samples were analysed using a HPLC-MS/MS assay; the IVIVC analyses comparing the two results were performed using WinNonlin.

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This study investigated absorption of nevirapine (NVP) from targeted sites of the gastrointestinal tract using remotely activated capsules and gamma scintigraphy. A total of 24 participants were randomized to receive 50 mg NVP orally as a suspension or via remotely activated capsules for release into the ascending colon. The 24 participants were then rerandomized into parallel groups of n = 8 for drug release into the ileum, jejunum, or descending colon.

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Nevirapine is a nonnucleoside reverse transcriptase inhibitor used as part of combination therapy for human immunodeficiency virus (HIV) infection. Nevirapine may be prescribed for patients with hepatic fibrosis and cirrhosis. Significant autoinduction of cytochrome P450 3A4 and 2B6 following multiple dosing prompted an assessment of the metabolic profiles in patients with liver disease receiving chronic nevirapine therapy.

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The pharmacokinetics and safety of BILR 355 following oral repeated dosing coadministered with low doses of ritonavir (RTV) were investigated in 12 cohorts of healthy male volunteers with a ratio of 6 to 2 for BILR 355 versus the placebo. BILR 355 was given once a day (QD) coadministered with 100 mg RTV (BILR 355/r) at 5 to 50 mg in a polyethylene glycol solution or at 50 to 250 mg as tablets. BILR 355 tablets were also dosed at 150 mg twice a day (BID) coadministered with 100 mg RTV QD or BID.

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BILR 355 is a second-generation nonnucleoside reverse transcriptase inhibitor (NNRTI) under clinical development for the treatment of human immunodeficiency virus infection, particularly in those who harbor virus resistant to the currently available NNRTIs. Two single-center, double-blinded, placebo-controlled, parallel dose-escalation studies were conducted to evaluate the pharmacokinetics and safety of oral BILR 355 administration alone and after coadministration with ritonavir (RTV) at 100 mg. Following a single dose of BILR 355 in oral solution, the mean half life (t(1/2)) was 2 to 4 h, with peak concentrations occurring at 0.

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Background: Given the limited treatment options for patients with high-level resistance, antiretroviral (ARV) regimens based on concomitant use of 2 ritonavir (RTV)-boosted protease inhibitors (PIs) were considered a therapeutic option.

Methods: Boehringer Ingelheim (BI) study 1182.51 examined the pharmacokinetic profile, safety, and efficacy of RTV-boosted tipranavir (TPV/r), alone and in combination with comparator PIs (CPIs) in 315 triple-class-experienced, HIV-infected patients.

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